1. Field of the Invention
The invention relates to ear bud earphones and speakers, including headphones, and headsets, especially for mobile and hands free operation, and for the retention of the headphones, headsets, and earphones during physical activity and movement by the user. In one embodiment the subject earphones have a system, structure, or process for converting an information signal from audible acoustic sound vibrations to corresponding time-varying electrical quantities. The earphone is intended to be placed in or over the user's ear canal, that is, sealably within the concha or ear canal. This serves to acoustically isolate the ear canal from a noisy environment. This is to provide for a high degree of miniaturization and unobtrusiveness with a minimum amount of amplification, and associated noise and distortion. Included are earphones where a small sound reproducing system, that is, an output transducer, transmits signals directly into the ear canal to increase the sound level received by the ear. Signals may be electromagnetic signals conveyed to the earphones by conductors, electromagnetic signals conveyed to the earphone without the use of conductors, such as by modulated RF or infrared carrier, and acoustic signals conveyed to the earphones by tube or conduit.
2. Background Art
Sound devices such as earphones and headphones are used extensively throughout the world. One style of earphone that is commonly used is referred to as an ear bud or an ear bud-type headphone. Ear buds are small speaker-like devices that are designed to fit within the external ear, that is, the concha or ear canal, of a user so that the user can listen to sound being transmitted from a sound source with a degree of acoustic isolation from environmental sound pollution. Some examples of typical sound sources where ear buds may be used include personal and/or portable audio players (including radios, cassette players, compact disc players, portable mp3 players, etc.), portable DVD players, telephones (including wireless and cellular type telephones), two way radios, etc. When properly positioned in the ear, ear buds can provide the listener with acceptable sound transmission to the ear canal. However, due to person-to-person variations and variations in the environment in which the ear buds are used, fit may not be adequate and extraneous noise may make transmission inadequate. In addition, improper fit can greatly degrade the sound quality (level and frequency response). This is particularly important when listening to music.
A wide variety of headphones and ear bud earphones have been developed as well as a number of adapters and prostheses attachable to these devices. In addition, a wide variety of methods for manufacturing headphones (including ear buds) and adapters have been developed. Among these known devices and methods, each has certain advantages and disadvantages. There is an ongoing need to provide alternative devices and methods for making these devices which improve sound transmission, isolate extraneous noise and provide improved comfort and fit.
One problem of ear bud speakers and ear insert headsets, e.g., speakers that are supported predominantly or solely by friction in the ear canal, are typically unstable and easily fall out. Some headphones can be retained this way but once a microphone boom is added an additional form of retention is required.
In addition to the problem of holding the earphone in the ear, there is also a problem of keeping good acoustic coupling of the speaker ear tip to the ear canal. Gravity and movement of the user tends to loosen the speaker ear tip and cause it to fall either down into the concha or entirely out of the ear. Keeping good coupling is particularly important if the speaker is using a sealed design.
There are numerous miniature speaker and ear bud products on the market. Many of these ear bud speaker products use ear bud insert type speakers, as ear bud speakers, that are designed to form a seal in the ear. The seal may be effected by, for example, deformation of the ear canal and speaker for a friction seal, and by a pressure differential between the atmosphere and the ear canal as well as by the physical properties of both the ear canal and the ear bud speakers. Most ear bud speakers that attempt to use only friction to hold the headset in place work very poorly. Speakers may also incorporate a microphone boom. The microphone boom only exacerbates the problem of earphone retention.
One application of ear bud earphones is for hearing aids. One of the most persistent and annoying problems facing users of hearing aids is feedback, which is perceived by the user as a high pitched high volume whistling in the ear. While feedback can be a problem with behind-the-ear hearing aids it is particularly prevalent with in-the-ear hearing aids where the microphone and the speaker are in relatively close proximity. Previously this has resulted in a more complicated hearing aid design and increased cost. Various mechanical approaches have also been taken such as ear-molds and hollow cylinder gaskets. Ear-molds must be custom fitted to each user's uniquely shaped ear anatomy, that is the pinna encompassing the helix and anti-helix, and the concha. The need for individually fitting and molding adds to the cost.
Attempts to address this issue with, for example, gaskets and O-rings have not been completely satisfactory. Gaskets and O-rings tend to slide off the end of the hearing aid when the hearing aid is removed from the ear. This tendency is exacerbated by perspiration, ear wax or other lubricants that find their way between the hearing aid and the gasket or O-ring. An O-ring or gasket that slips off can easily get lost or even worse can pose a serious medical problem if it gets trapped or lost inside the ear canal, resulting in a negative esthetic.
Thus, a need exists for a compact ear bud speaker that is readily retained in, and easily removable from, the ear canal.